Brush-holder for dynamo-electric machines.



J. E. WEBSTER; BRUSH HOLDER FOR DYNAMO ur'moumx rum) IAN. 3, 19 06.

ammo MACHINES.

RENEWED, MAY 19, 1909.

Patented Aug. 3, 1909.

WITNESSES:

UNITED STATES PATENT, oFFIG ionn E. wEBsTEaor PITTSBURG, 'PENNSYJJVANIA, ASSIGN'OR-TO &' MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

e nifsn-nonnnnronDYNAMo-nL o'rRIo MACHINES.

f ind. 930,007. j

I Sp ecifieation-ofLetters Patent.

I .AppIicaifion filed Januar a, ieoasena'l 11%. 294,416; Renewed May 19, 909. Serial no. 497,108.

Toall whom it mo concern: 4

Be it known that I, Joan E. WEBSTER,

'a citizen of-thef United States, and a resident of Pittsburg, in the county of Allegheny' and State of Pennsylvania, haveinvented ahnewand useful Improvement .in

Brush-Holders for 'Dynamo-Ele'ctric Machines, of which the following is a specifi- .cation;

M l invention relates tothe support and 'ins'uation of current-carrying parts for dynamo-electric machines and has special referenceto means for insulating and sup; porting brush holders.

The object of my invention is to provide means of,the nature above specified that shall-be simple anddurable in construction;

that shall specially protect and preserve the insulation and that shall permit of proper adjustment of the holder.

As it is often desirable and convenient to support the brush holdersof a dynamoelectric machine from some part of the frame, it becomes essential to provide adequate insulation in order to prevent the grounding of the current-carrying parts,

and it is usually desirable to so mount the brush holder that a radial-adjustment may be effected, relative to the rotating part.

In. the prior art, it hasbeen usual, particularly with railway motors, to support the brushholde'r by an armor'shank of substantially square cross-section so that the holder could be held in position by means of a clamp comprising two V-shaped parts, one of which was rigidly attached to or integral with the portion of the frame from which the holder was supported. In this case, the square arm or shank was coveredwith a film or- Wrapping of insulating material, but, on account of variations inthe osition of the holder, and also'by reason o the strains to which the holder was subjected, the insulating wrappingoften showed a tendency.

to crack at the. corners or become worn away to such an extent that, its insulating qualities as porcelain, may be fitted over the shanks in order to limit the distance which with wrappings of insulating material, such" as mica, and for the protection of the nsulation from deterioration either by contact with the air; or b abrasion against the inner 55.

surfaces'of the .c amp by which the holderis wnsrmenousn ELECTRIC.

Patented. Aug. 3, 1909.

held in position, sealing tubes of suitable material and sufficiently thin to readily conform to the shape of the surfaces between which they. are clamped are placed over the vention and F ig; 2 is .a cross section, on the line IIII.

, of-v the supporting means shown in Fig. l. Referring to the drawings, the brush holder illustrated therein comprises a -.car-

hon-holding 'boxand spring support 1, which s arranged to recelve one or more carbon bnushes 2, and a plurality of cylindrical supporting arms or shanks 4 and 5, which, in combination with a clamp 7 and a bolt-8,

serve .to fasten the brush holder, as a Whole,

to a ledge 6 with which the frame ofthemachine is provided, as is usual in railway vehicle motors. The clamp 7 comprises a'pair of complementary blocks which areprovldedi' with parallel, semi-cylindrical greoves to re; ceive the shanks 4 and 5 and. arefastened; together and to-the ledge-6 by the bolt 8 which passes through'a hole near the center of the blocks and is screwed into the-ledge.

By loosening'the bolt 8, the'brush holder may be adjusted in a plane parallel to the center lines of the arms or shanks 4 and 5,

'andlin order to preventthe grounding of the brush holder through the motor frame,

the shanks are covered with a wrapping 10 of insulating.fmaterial, such as mica.

wra in 10 is J-rotected from abrasion and PP b l from-deterioration by Contact with the air by'caps 11 of suitable material, such as brass.

The caps 11 are preferably made sufiiciently thin to readily yield, 'when compressed,and are fitted closely over theinsulating tubesin order that the shanks ,maybe securely held against accidental lon itudinal. movement. Collars 12 of hard insu ating material, such may project into the clamp It will be observed that, .while theta-. 92, porting shanks are cylindrical and :wltlite a longitudinal adjustment of the brush h relative" to its support ispermitted, an im esirable' rotary "movement of the holder is preventedlby the use of Itizvoshanksi "A d'er;

uate insulation of these parts may, there ore, be readily and effectively provided wi thout; introducing any of the disadvana tagesin'cident to the use of a brush holder having a single square or cylindrical shank.

A brushyholder pressure mechanism 13 ,comprisesashaft .14: which is attached .to the frame 1, a sleeve 15, that is rotatably mounted thereon and is provided with a ratchet wheel 16, and a brush-engaging finger 17 which is rotatably mounted on-the sleeve15 and is provided with a pawl 18 to engage the ratchet wh'eel16'. A spiral spring 19 is coiled about the-sleeve 15, its inner extremity engaginga longitudinal groove 20 in the "sleeve 15 and its outer extreniityfQl being held stationary by engagement with the hooked projection'EQ on the frame 1. A guide web 23, which may be anintegral part the sleeve 15. The finger 17 is provided.- 1 1 5 with a flexibleimembenfilj having an, end -,piece which is held against the outer end ofthe brush by the pnessureiof the spring 19,, the degree of pressdre. being adjusted 'by I '1 machines, tllGCOXQlJIIlttflOIl with a plurality .{;;of -su i porting'arms and insulating sleeves means of the pawl- 18 and'the ratchet 16';

he engaging surface oif} ,he...-ledge=6--'may.l.'be2 overed with aflayer o Babbittmetal or "er similarmaterial so that'the-lower. clamping plate may more readily seat itself when pressure is applied by'means of the 'bolt8.'-'

Although I have shown insulating and supporting means constructed in accordance with my invention as -applied only in connection with brush holders which are -adapt' dfor use with railway vehicle motors, such ineansmay, of course, be applied to any type of brush holder. which is s mi larly supported, and I -desire that variations which do not depart from the spirit of my invention shall be included Within its scope.

' I claim as my invention: 1 1. Ina brush holder, the combination with or the frame, extends'from the projection 22- a pair of'parallel and cylindrical' supporting arms or projections, insulating tubes severally closed atone end and fitted over said encircling the tubes near their open ends, of

5b pro ections, and insulating stops or collars thin metal caps fitted over the tubes and abutting against the stops or collars.

2. In a brush holder the combination with a pair of parallel and cylindrical supporting" arms or projections, and insulating tubes severally closed at one end and fitted oversaid projections, of thin metal caps fitted over the insulating tubes to protect and seal.

the insulation.

3. In a brush holder for dynamo-electric .machines,"the combination with a plurality of supporting arms and insulating sleeves therefor severallyclosed atone end, of seal- .ing and protecting caps or sheaths for-the insulating sleeves, and means for rigidly mounting the brush holder. 4. In-a brush holder for dynamo-electric machines, the combination with supporting arms or projections of conducting materia .insulating'tubes' severally closed at one end and fitted onto the projections, ofa thin metal cap fitted closely over each insulating tube,- and a two-part clamp-or cleat for securing the brush holder to a rigid body;

5.v In a brush holder for dynau o ele'ctric and fitted over said arm, of a metal cap or sheath fitted over the insulating tube, and a clamp engaging the outside of the ca securing the arm .to a rigid body, sai cap or sheath being sufficiently thin to conform to the surfaces which engage it.

for

In testimony whereof, 'I- have hereunto subscribed my; name {this 28th dayv of Deicember, 1905. a

v JOHN E. WEBSTER. Witnesses: f v v v M. MACLAREN,

. 1 .Bmnnrflrnns, 

